The Red Devils have confirmed that the deal for the Switzerland-born versatile right-sided player was concluded before the transfer window closed on Monday for an undisclosed fee.

Janko becomes the third player to arrive at the club during the summer following the arrival of talented young defender Guillermo Varela, and Marouane Fellaini who joined from Everton for £27.5 million.

The club revealed that Janko impressed Reds representatives earlier in the year during the Blue Stars Tournament where he played against United.

He also took part in a trial for the club and can play in a number of different positions but is most likely to be used as a full-back when he joins up with United’s Under-18 squad.

The Premier League champions failed to land two other targets on the final day of the transfer window with Ander Herrera and Fabio Coentrao both remaining in La Liga with Athletic Bilbao and Real Madrid respectively.